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Elevational patterns of warming effects on plant community and topsoil properties: focus on subalpine meadows ecosystem

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Journal of Mountain Science 2024年第1期21卷 146-159页

作者： hao aihua LUO Zhengming CHEN Xiaojiang Department of Geography Xinzhou Normal UniversityXinzhou 034000China Department of Biological Sciences Xinzhou Normal UniversityXinzhou 034000China

Climate warming profoundly affects plant biodiversity, community productivity, and soil properties in alpine and subalpine grassland ecosystems. However, these effects are poorly understood across elevational gradients in subalpine meadow ecosystems. To reveal the elevational patterns of warming effects on plant biodiversity, community structure, productivity, and soil properties, we conducted a warming experiment using open-top chambers from August 2019 to August 2022 at high(2764 m a. s. l.), medium(2631 m a. s. l.), and low(2544 m a. s. l.) elevational gradients on a subalpine meadow slope of Mount Wutai, Northern China. Our results showed that three years of warming significantly increased topsoil temperature but significantly decreased topsoil moisture at all elevations(P<0.05), and the percentage of increasing temperature and decreasing moisture both gradually raised with elevation lifting. Warming-induced decreasing proportions of soil organic carbon(SOC, by 19.24%), and total nitrogen(TN, by 24.56%) were the greatest at high elevational gradients. Experimental warming did not affect topsoil C: N, p H, NO_(3)^(-)-N, or NH_(4)^(+)-N at the three elevational gradients. Warming significantly increased species richness(P<0.01) and Shannon-Weiner index(P<0.05) at low elevational gradients but significantly decreased belowground biomass(P<0.05) at a depth of 0–10 cm at three elevational gradients. Warming caused significant increases in the aboveground biomass in the three elevational plots. Warming significantly increased the aboveground biomass of graminoids in medium(by 92.47%) and low(by 98.25%) elevational gradients, that of sedges in high(by 72.44%) and medium(by 57.16%) elevational plots, and that of forbs in high(by 75.88%), medium(by 34.38%), and low(by 74.95%) elevational plots. Species richness had significant linear correlations with SOC, TN, and C: N(P<0.05), but significant nonlinear responses to soil temperature and soil moisture in the warmed treatm

关键词： Warming effect Plant diversity pattern Community structure change Elevation gradient Alpine meadow ecosystem Mount Wutai

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Defining a highly conserved cryptic epitope for antibody recognition of SARS-CoV-2 variants

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Signal Transduction and Targeted Therapy 2023年第8期8卷 3567-3569页

作者： aihua hao Wenping Song Cheng Li Xiang Zhang Chao Tu Xun Wang Pengfei Wang Yanling Wu Tianlei Ying Lei Sun MOE/NHC/CAMS Key Laboratory of Medical Molecular Virology Shanghai Institute of Infectious Disease and BiosecurityShanghai Frontiers Science Center of Pathogenic Microorganisms and InfectionShanghai Engineering Research Center for Synthetic ImmunologyShanghai Fifth People’s HospitalInstitutes of Biomedical SciencesSchool of Basic Medical SciencesFudan UniversityShanghaiChina Biomissile Corporation ShanghaiChina State Key Laboratory of Genetic Engineering Shanghai Institute of Infectious Disease and BiosecuritySchool of Life SciencesFudan UniversityShanghaiChina

Dear Editor,In recent months,additional Omicron variants of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),including the BA.5 sublineage BF.7 and BQ.1.1 and the BA.2 linage recombination XBB,XBB.1.5 and XBB.1.16,have emerged following the BA.2 and BA.5 ***,BQ.1.1 and XBB showed substantial neutralization escape as compared with the previous variants,and have gradually become the dominant variants worldwide.1 These facts emphasize the urgency of identifying highly conserved SARS-CoV-2 epitopes,which would be essential for the design of universal vaccines and broadly neutralizing antibodies.

关键词： acute variants conserved

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Enhancing SAEAs with unevaluated solutions:a case study of relation model for expensive optimization

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Science China(Information Sciences) 2024年第2期67卷 41-58页

作者： hao hao Xiaoqun ZHANG Aimin ZHOU Institute of Natural Sciences Shanghai Jiao Tong University Shanghai Frontiers Science Center of Molecule Intelligent Syntheses School of Computer Science and Technology East China Normal University

Surrogate-assisted evolutionary algorithms(SAEAs) hold significant importance in resolving expensive optimization problems. Extensive efforts have been devoted to improving the efficiency of SAEAs through the development of proficient model-assisted solution selection methods, which, however, first requires generating high-quality solutions. The fundamental paradigm of evaluating a limited number of solutions in each generation within SAEAs reduces the variance of adjacent populations, thereby affecting the quality of offspring solutions. This is a frequently encountered issue yet receives little attention. To address the issue, this paper presents a framework using unevaluated solutions to enhance the efficiency of *** surrogate model is employed to identify high-quality solutions for the direct generation of new solutions without evaluation. To ensure dependable selection, we have introduced two tailored relation models to select the optimal solution and the unevaluated population. A comprehensive experimental analysis is performed on two test suites, which showcases the superiority of the relation model over regression and classification models in the solution selection phase. Furthermore, the surrogate-selected unevaluated solutions with high potential have been shown to enhance the efficiency of the algorithm significantly.

关键词： expensive optimization unevaluated solutions relation model surrogate-assisted evolutionary algorithm

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A Global Optimality Principle for Fully Coupled Mean-field Control Systems

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 379-413页

作者： Tao hao School of Statistics and Mathematics Shandong University of Finance and EconomicsJinan 250014China

This paper concerns a global optimality principle for fully coupled mean-field control *** the first-order and the second-order variational equations are fully coupled mean-field linear FBSDEs. A new linear relation is introduced, with which we successfully decouple the fully coupled first-order variational equations. We give a new second-order expansion of Y^(ε) that can work well in mean-field framework. Based on this result, the stochastic maximum principle is proved. The comparison with the stochastic maximum principle for controlled mean-field stochastic differential equations is supplied.

关键词： optimal control global maximum principle fully coupled general mean-field FBSDE adjoint equation recursive utility

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Effect of CO_(2) Opposing Multiple Jets on Thermoacoustic Instability and NO_(x) Emissions in a Lean-Premixed Model Combustor

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Journal of Thermal Science 2024年第1期33卷 207-221页

作者： ZHOU hao HU Liubin Institute for Thermal Power Engineering State Key Laboratory of Clean Energy UtilizationZhejiang UniversityHangzhou 310027China

This paper experimentally studied the effect of CO_(2) opposing multiple jets on the thermoacoustic instability and NO_(x) emissions in a lean-premixed model *** feasibility was verified from three variables:the CO_(2) jet flow rate,hole numbers,and hole diameters of the *** indicate that the control effect of thermoacoustic instability and NO_x emissions show a reverse trend with the increase of open area ratio on the whole,and the optimal jet flow rate range is 1-4 L/min with CO_(2) opposing multiple *** this flow rate range,the amplitude and frequency of the dynamic pressure and heat release signals CH~* basically decrease as the CO_(2) flow rate increases,which avoids high-frequency and high-amplitude thermoacoustic *** amplitude-damped ratio of dynamic pressure and CH*can reach as high as 98.75% and 93.64% with an optimal open area ratio of 3.72%.NO_(x) emissions also decrease as the jet flow rate increases,and the maximum suppression ratio can reach 68.14%.Besides,the flame shape changes from a steep inverted "V" to a more flat "M",and the flame length will become shorter with CO_(2) opposing multiple *** research achieved the synchronous control of thermoacoustic instability and NO_(x) emissions,which could be a design reference for constructing a safer and cleaner combustor.

关键词： thermoacoustic instability lean-premixed model combustor CO_(2)opposing multiple jets open area ratio NO_(x)emissions

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青藏高原典型草地NDVI时空演变的季节差异及其气候驱动

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生态学报 2023年第1期43卷 352-363页

作者：郝爱华薛娴段翰晨彭飞尤全刚忻州师范学院地理系忻州034000 中国科学院西北生态环境资源研究院沙漠与沙漠化重点实验室兰州730000

基于全球库存建模和制图研究(GIMMS)第三代归一化植被指数(NDVI3g)产品和气象数据,利用一元线性回归模型、偏相关分析和显著性T检验,分析了1982—2015年青藏高原高寒草甸和高寒草原春、夏、秋季NDVI时空演变的差异特征及其与气候因子的... 详细信息

基于全球库存建模和制图研究(GIMMS)第三代归一化植被指数(NDVI3g)产品和气象数据,利用一元线性回归模型、偏相关分析和显著性T检验,分析了1982—2015年青藏高原高寒草甸和高寒草原春、夏、秋季NDVI时空演变的差异特征及其与气候因子的关系。研究表明:(1)高寒草甸春、夏、秋季NDVI整体均无明显变化趋势,高寒草原春季和夏季NDVI均显著增加,变化速率均为0.0002/a(P<0.05),而秋季NDVI变化趋势不明显。(2)空间上,高寒草甸春季NDVI显著增加面积占比31.95%,集中分布在祁连山区和三江源区,夏季NDVI显著增加的面积占比32.12%,主要分布在祁连山区、三江源地区和一江两河流域;秋季NDVI显著增加的比例为24.59%,集中分布于祁连山区和一江两河流域。高寒草原春、夏、秋季NDVI显著增加的区域均集中分布于西藏自治区北部和柴达木盆地南缘地区,分别占比44.20%、43.09%和37.99%。(3)高寒草甸春季和秋季NDVI均与气温显著正相关,偏相关系数达0.41(P<0.05)和0.23(P<0.05),夏季NDVI与气温、降水量和太阳辐射均呈显著相关性,偏相关系数分别为0.35(P<0.01)、0.56(P<0.01)和-0.57(P<0.01);高寒草原春季NDVI与气温和降水量均呈显著正相关,且与降水量偏相关系数较高,为0.31(P<0.05),夏季NDVI与气温、降水量和太阳辐射均呈显著相关性,与降水量偏相关系数最高,为0.46(P<0.01),秋季NDVI与太阳辐射显著正相关。(4)空间上高寒草甸春季和秋季NDVI与气温呈正相关的像元分别占比76.50%和67.86%,集中于祁连山区和三江源区,夏季NDVI与降水量呈正相关的像元占比58.42%,与太阳辐射呈负相关的像元占比53.69%,均集中分布于祁连山区、三江源区和一江两河流域。高寒草原春季和夏季NDVI与降水量呈正相关的像元分别占比63.02%和67.62%,集中分布在西藏自治区西部和柴达木盆地南缘。研究可为保护青藏高原草地资源、管理高寒生态系统植被碳库以及推动青藏高原长效生态增汇提供科学依据。

关键词：归一化植被指数季节性高寒草地变化趋势青藏高原

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非平行光束光栅照明C-T成像光谱仪消像散研究与设计

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红外与激光工程 2015年第7期44卷 2132-2136页

作者：郝爱花胡炳樑中国科学院西安光学精密机械研究所光谱成像技术实验室陕西西安710119 西安邮电大学电子工程学院陕西西安710121 中国科学院大学北京100049

切尔尼-特纳(Czerny-Turner,C-T)光谱仪是光栅光谱仪中常用的光谱仪器。其结构紧凑,无非球面镜,常被用于单色仪和光谱辐射计中。对于成像光谱仪,像散是影响其空间分辨和光能利用的主要像差。就非平行光束光栅照明像散校正方法进行了理... 详细信息

切尔尼-特纳(Czerny-Turner,C-T)光谱仪是光栅光谱仪中常用的光谱仪器。其结构紧凑,无非球面镜,常被用于单色仪和光谱辐射计中。对于成像光谱仪,像散是影响其空间分辨和光能利用的主要像差。就非平行光束光栅照明像散校正方法进行了理论分析和实验验证,提出会聚和发散光栅照明C-T成像光谱仪都可以进行像散校正,其根本取决于光栅入射角和衍射的余弦平方比大于或小于1,大于1对应发散照明消像散,小于1则对应会聚照明消像散。

关键词：会聚照明 C-T成像光谱仪像散

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Research progresses and prospects of multi-sphere compound extremes from the Earth System perspective

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Science China Earth Sciences 2024年第2期67卷 343-374页

作者： Zengchao hao Yang CHEN College of Water Sciences Beijing Normal UniversityBeijing100875China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing100081China

Compound extremes,whose socioeconomic and ecological impacts are severer than that caused by each event occurring in isolation,have evolved into a hot topic in Earth Science in the past *** the context of climate change,many compound extremes have exhibited increasing frequency and intensity,and shown novel fashions of combinations,posing more pressing demands and tougher challenges to scientific research and disaster prevention and *** article,via a perspective of multi-sphere interactions within the Earth System,systematically reviews the status quo,new scientific understanding,and deficiencies regarding the definition,mechanism,change,attribution,and projection of compound *** study also sorts out existing challenges and outlines a potential roadmap in advancing the study on compound extremes with respect to data requirement,mechanistic diagnosis,numerical modeling,attribution and projection,risk assessment,and adaptive *** directions of compound extremes studies and key research topics that warrant multi-disciplinary and multisectoral coordinated efforts are also *** that climate change has reshaped the type of extremes,a transformation from the traditional single-event perspective to a compound-event perspective is needed for scientific research,disaster prevention and mitigation,and climate change adaptation,calling for bottom-up innovation in research objects,ideas,and *** article will add value to promoting the research on compound extremes and interdisciplinary cooperations.

关键词： Extremes Compound extremes Climate change and risk Multi-sphere interactions

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GLOBAL SOLUTIONS IN THE CRITICAL SOBOLEV SPACE FOR THE LANDAU EQUATION

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Acta Mathematica Scientia 2024年第4期44卷 1347-1372页

作者： hao WANG Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China

The Landau equation is studied for hard potential with-2≤γ≤*** a perturbation setting,a unique global solution of the Cauchy problem to the Landau equation is established in a critical Sobolev space H_(x)^(d)L_(v)^(2)(d>3/2),which extends the results of[11]in the torus domain to the whole space R_(x)^(3).Here we utilize the pseudo-differential calculus to derive our desired result.

关键词： Landau equation nonlinear energy method global existence pseudo-differential calculus

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Study of the multi-physics field-coupled model of the two-stage electrostatic precipitator

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Building Simulation 2024年第3期17卷 387-398页

作者： Wenjia hao Yu Guo Yukun Wang Tao Yu hao Gao Zhengwei Long Tianjin Key Laboratory of Indoor Air Environmental Quality Control School of Environmental Science and EngineeringTianjin UniversityWeijin Road 92Tianjin300072China Wuhan Second Ship Design and Research Institute WuhanChin

The two-stage electrostatic precipitator is widely used to purify oil mist ***,there is limited research on the influences of relative humidity,particle deposition characteristics,and the generation of gaseous ***,this paper established a numerical model of the electrostatic oil mist purifier and applied it to a two-stage electrostatic *** the model was used to investigate the corona discharge characteristics under different relative humidity conditions in the charged zone,the particle deposition characteristics,the purification efficiency,the ozone concentration distribution,and the oil vapor concentration distribution in the collection *** results indicate that,with a constant temperature,the corona current decreases as relative humidity increase,and there is a quadratic relationship between relative humidity and *** variation in relative humidity has little impact on the purification *** maximum ozone concentration occurs near the electrode line,and its concentration is influenced by the discharge current and inlet airflow *** oil vapor concentration reaches its maximum value at the side plates,with a value of 19 ppb,while it reaches the minimum value at the collecting zone electrode plate,with a value of 2 *** temperature is the main factor affecting the volatilization of the oil film,with higher temperatures resulting in higher oil vapor.

关键词： two-stage ESPs particle deposition corona discharge oil vapor

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